Kbase P58614: Session hangs if Progress fails to open a busy file.
| Autor |
Progress Software Corporation - Progress |
| Acesso |
Público |
| Publicação |
20/01/2004 |
|
Status: Unverified
SYMPTOM(s):
Progress 4GL session hangs executing the 4GL OUTPUT TO statement.
Running code similar to the following hangs the session.
DO ON ERROR UNDO, RETRY:
IF RETRY THEN DO:
/* Error logging + evasive action*/
LEAVE.
END.
OUTPUT TO myfile.txt.
END.
CAUSE:
The file "myfile.txt" is busy or otherwise unavailable to the session.
FIX:
Since the syntax of the Progress 4GL OUTPUT TO statement does not allow the NO-ERROR option, a possible solution here is to redirect the generated errors to an an error message log file for subsequent processing:
DEFINE VARIABLE cVariable AS CHARACTER NO-UNDO.
DEFINE STREAM ErrorStream.
DEFINE STREAM OutputStream.
OUTPUT STREAM ErrorStream TO "ErrorMessage.log" KEEP-MESSAGES.
MainBlock:
DO ON ERROR UNDO, RETRY:
IF RETRY THEN DO:
OUTPUT STREAM OutputStream CLOSE.
OUTPUT STREAM ErrorStream CLOSE.
LEAVE MainBlock.
END.
OUTPUT STREAM OutputStream TO myfile.txt.
END.
INPUT FROM VALUE("ErrorMessage.log") NO-ECHO.
IMPORT UNFORMATTED cVariable.
/* Replace following message statement with code */
/* for corrective action based on error message */
MESSAGE cVariable
VIEW-AS ALERT-BOX INFO BUTTONS OK.
INPUT CLOSE.